[Ron Sutton]

Alrighty then ... let's talk Roll Centers.

I’ll be very basic for any readers following along that are completely new to this & apologize in advance for boring the veterans with more knowledge of this. Cars have two roll centers … one as part of the front suspension & one as part of the rear suspension. I’ll first explain what role they play in the handling of a car … then how to calculate them … and finally how to tune with them.

Think of the front & rear roll centers as pivot points. When the car experiences body roll during cornering … everything above that pivot point rotates towards the outside of the corner … and everything below the pivot point rotates the opposite direction, towards the inside of the corner. Because the front & rear roll centers are often at different heights, the car rolls on different pivot points front & rear … “typically” higher in the rear & lower in the front.

If you were to draw a line parallel down the middle of the car connecting the two roll centers … this is called the "roll axis" … that line would represent the pivot angle the car rolls on … again “typically” higher in the rear & lower in the front.


.